What no one is talking about is how the old vaccine got made. No vaccine production is very pretty (whooping cough uses the mucus of infected children, typhoid, the excrement of victims), but this is one of the few derived from human blood specifically, the blood products of homosexual men who have had hepatitis.
This vaccine was replaced in the early 1990s by a genetically engineered, or "recombinant" version of the vaccine, which is grown on yeast cells. However, the earlier plasma derived vaccine was never withdrawn, and even those drug companies which stopped producing the blood derived product kept selling it until it was used up. So until very recently anyone receiving the vaccine could have received a blood based product.The New York Blood Center addressed this issue by studying hundreds of cases in low and high risk populations receiving the vaccine. Their conclusion: no one is at a higher risk of developing AIDS from the hepatitis B vaccine.
Those in favour of the vaccine argue that the process that kills the hepatitis virus also kills any other viruses lurking about. But remember: at the moment, many high level scientists, including the co-discoverer of the AIDS virus, are questioning whether AIDS is caused by a single virus. It's entirely possible that a number of cofactors in the blood causing or contributing to AIDS which we don't currently understand may not be killed by this process. The Health Secretary in his announcement called this vaccine "perfectly safe". Until we understand what causes AIDS, no one can make that statement with certainly.
Speaking of AIDS, another problem with the HB shot, according to several scientists in the Department of Microbiology at Loma Linda University in California, is that patients vaccinated for hepatitis B sometimes give a false positive reading on an HIV test.